The present invention relates to the invention disclosed in European Patent EP 0120263 that is incorporated by reference. This Patent model test measurements madden at the Athens Technical University wind tunnel during 1993 (see table 1 of page 2) proved the insufficiency of frontal depression by friction.
The supersonic propeller model test measurements madden on the same wind tunnel during 1994 (see table 2 of page 3) proved the substantial improvement of frontal depression by vertical blades, as shown on FIG. 1 here after.
1. Field of the Invention
The field of the invention is the flight of air-vehicle by frontal depression, more intense than that of rear air stream separation zone, instead of the conventional very strong rear overpressure, which is also more expensive. This aeronautic area has not been explored or exploited even it present very interesting characteristics, especially economical.
The frontal depression is secured by adding in the frontal impact zone an horizontal rotation speed on the thin air boundary layer, eliminating any overpressure on that zone, and without effecting the general air flow around the stream lined air-vehicle fuselage. Theorycaly this is based on the non vector of Bernouilli Theorem       P    +          p      ⁢                        v          2                2              =  C
2. Description of Prior Art
Air vehicle motion elements can be classified in two broad areas.
The first area includes the axial flow propellers, having a perimeter speed limit of Mach one, and an efficiency factor less than 70% consequently their impulsion speed is only subsonic.
The second area includes the radial flow of multi step turbofans, having a supersonic impulsion speed up to about 2.5 Mach but with an excessive fuel consumption.
To remedy this drawback the wind-tunnel test measures made on EU 0120263 Patent model of table 1 and of FIG. 1 and of FIG. 2 have been considered, indicating that:
The additional side speed to the frontal air flow by only the smooth surface friction of the rotating impeller proved to be insufficient.
Patented helicoplane model tested mesures dated Apr. 1, 1993, done on air tunnel of the Technical University of Athens.
Advanced helicoplane model tested mesures dated Feb. 25, 1994, done on the air tunnel of the Technical University of Athens.
Accordingly a
1. SIMPLE SUPERSONIC PROPELLER (FIGS. 9.10.11) is constituted by an horizontal streamlined shell of thin profile and reduced drag, having an upper semiellipsoid convex boundary (1) and a lower slightly convex boundary (2) with a central to the axis, supported by bearings, on which is fixed an impeller of semiellipsoid surface (4) full of vertical very dense and of short width (4 mm) blades (4), which secure the side speed of the tangential air layer through the large front opening (4) on the impact area, and the respective frontal depression, according to Bernoulli theorem, creating the horizontal motion which can reach even a supersonic speed. The impeller axis is connected to the motor by cogwheels (10) clutches (11) and gear box (12) permitting the increase of the imperial rotation. The propeller is fixed by rafters (13).
2. COMPOSITE SUPERSONIC PROPELLER (FIGS. 4,5,6) In order the above mentioned supersonic propeller has to have also lifting capability as a single step blower, is equipped additionally with internal tilted lifting blades (5) on the internal concave site of it, with a circular opening (6) close to the rotation axis equipped with deflector vanes (6) and obstruction vanes (7), (8) permitting the blower to create a vertical air flow. These are closed when the air-vehicle wings attain a wing lifting force equal to the air vehicle weight. And finally it includes the rafters connecting the supersonic propeller to the air vehicle fuselage.
The lower light convex boundary is characterized by a perimeter opening (7) equipped with deflector vanes and the rafters connecting the air vehicle fuselage, to the propeller and its wings.
The rear obstruction vane (8) when closed it reinstates the semi ellipsoid profile of upper propeller shell profile.
3. VTOVL AIR VEHICLE WITH SUPERSONIC PROPELLERS (Composite) A pair of supersonic propellers as in previous paragraph (1), is incorporated on the opposite sides (FIG. 3) of its fuselage with the propellers gravity center, coinciding with the air-vehicle weight gravity center and the wing area surface center. These are connected to the air-vehicle fuselage and the adjacent wings by rafters (13) and with their front totally uncovered. Also a small horizontal axial propeller is to place beyond the air vehicle direction blade, for balancing the yawing during vertical flight.
4. HEAVY VTOVL AIR-VEHICLE WITH SUPERSONIC PROPELLERS (Composite) This has two pairs of supersonic propellers as previous paragraph 1. The frontal is placed been at a lower level, the rear one at a higher level. These are incorporated in the opposite sides (FIG. 7) of its fuselage, with the propellers gravity center coinciding with the air vehicle weight gravity center and the wing area surface center, connected to the fuselage and the adjacent wings by rafters (13) and with their front totally uncovered. Rear horizontal axial propeller is not required.
5. LIGHT AIR VEHICLE WITH SIMPLE SUPERSONIC PROPELLERS (Simple) This has its own takeoff capability and has one pair of simple supersonic propellers (FIGS. 8,9,10,11) as mentioned in the previous page in paragraph 2 but without the lifting capability of subparagraph 1.2, and without the circular openings with deflectors and obstruction vanes of subparagraph 1.3 and 1.4. The two simple supersonic propellers have to be incorporated on the opposite sides (FIG. 8) of its fuselage and are connected to it and to the adjacent wing by rafters (13) with their front totally uncovered and connected to the air vehicle motor by cogwheels, clutches and gear box.